Most Asian markets ended with gains, except for China where the Shanghai Composite dipped by 1.1% and the Shenzhen index edged down by 0.8%. Chinese markets have stabilized a bit after crashing earlier this month. The Shanghai index lost 14% in July.

"The last trading day of the month [brings the] risk of choppier than normal trading as institutional investors re-balance portfolios and funds adjust to fit around month end performance statistics," wrote Simon Smith, chief economist at FxPro, in a Friday note.

In early trading, the Aussie dollar and Canadian dollar were weaker, while the Swiss franc was firmer against most major currencies.

5. Economics: At 8:30 a.m. ET, the U.S. government will report whether workers' paychecks grew during the second quarter. For the first quarter, the Employment Cost Index showed wages and salaries were up 0.7%, slightly better than the 0.6% growth in the final quarter of 2014.

A final reading of July's Consumer Sentiment Index is also expected at 10 a.m. from the University of Michigan. Preliminary numbers showed consumers were slightly less tempted to spend money this month.